Sri Lankan captain Angelo Mathews won the toss and chose to bat in the second one-day international against South Africa in Pallekele on Wednesday.
Both teams were unchanged from the opening game of the three-match series, which South Africa won by 75 runs.
The third and final one-dayer will be played in Hambantota on Sunday.
Sri Lanka: Angelo Mathews (capt), Lahiru Thirimanne, Tillakaratne Dilshan, Kusal Perera, Kumar Sangakkara, Mahela Jayawardene, Ashan Priyanjan, Sachithra Senanayake, Ajantha Mendis, Nuwan Kulasekara, Lasith Malinga.
South Africa: AB de Villiers (capt), Hashim Amla, Quinton de Kock, Jean-Paul Duminy, Imran Tahir, Jacques Kallis, Ryan Mclaren, David Miller, Morne Morkel, Vernon Philander, Dale Steyn.
Umpires: Nigel Llong (ENG), Ruchira Palliyaguruge (SRI)
TV umpire: Steve Davis (AUS)
Match referee: Jeff Crowe (NZL)